Lifting device



J. A. DIENNER LIFTING-DEVICE Sept. 2 124.

Filed 185mb so Patented Sept. 2, 1924.

UNITED STATES JOHN A. .DIENNER, OF CHICAGO, ILLINOIS.

LIFTING DEVICE.

Application filed March 30, 1921.

T 0 aZZ whom it may concern:

Be it known that I, Jenn A. DIENNER, a citizen of the United States, residing at Chicago, in the county of (look and State of Illinois, have invented certain new and useful Improvement in Lifting Devices, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming a part of this specification,

My invention relates to lifting devices, more particularly to devices for dumping the bodies of dumping trucks, and the like.

Numerous devices have heretofore been proposed ini-olving the use of two arms, which at some time during the lifting move ment, form a toggle. So far as I am aware, all such devices have operated on the wrong principle, namely, that they have begun the initial lifting effortwith a maximum angle bet-ween the toggle arms and the line of centers between which the toggle arms work.

It is the object of the present invention to provide a lifting device which shall operate on the correct theory of a toggle, namely, that the lifting effort shall be proportional to the co-tangent of the angle formed between the arm of th toggle and the line of centers of said toggle. in other words, the toggle is normally made, and moves from the made position to the broken position, as the load is lifted. It can be seen, therefore. that the amount of force required to move the load initially is relatively small, but tends to become greater as the load is raised. However, as the load is raised, the dumping effect lightens the load, and consequently the correct relations between lifting and dumping is maintained.

In order to acquaint those skilled in the art with the manner of constructing and operating a device embodying my invention, I shall now describe an en'ibodiment of the invention in connection with the accompanying drawings which form a part of the present specification.

Figure 1 is a. diagrammatic side elevational view of a device embodying my invention;

Figure 2 is, a. similar view of a modified form of the invention;

Figure 3 is a vertical cross sectional view taken on the line 3-3 of Figure 2; and,

Figure 4 is a fragmentary side view of a modified form of link.

In Figure 1 I have illustrated the simplest Serial No. 457,048.

form of the invention. The dumping "body 1 is mounted upon the "frame'2, by means of a suitablepivot 3, which .is placedin such a position that the load partly .rests uponithis pivot, and partly rests upon ablock 4,1atthe forward end of the device.

(in each side of the body and frame I provide a pair of togglelinksfi and'6, which arepivoted to the load 1 at thejpoint 7, and to the frame 2 at the point'8, respectively, and to eachother at the common "point 9. This common point 9 provides agyo'ke or'eye 10, to which a cable 11 is attached. I

The cable 11 is connectedto a drum '12 which is adapted to be operated by'means of the crank 13, or other suitable source of power, operating through'the gears 14 and 15. It is immaterial'how the winding means for the cable 11 is operated, or whether'the power be applied to the 'toggle'through a cable, since any other suitablemeans may be used. Power for this purpose maybe secured from the engine of a motor vehicle, or may be applied through an oil cylinder, or any other suitable means. It is to be understood that there are "two toggles, one on each side of the body and frame, and there may be two cables 11, or,

if desired, a single cable may be connected to the cross-bar between the pivot 9.

The operation of the device herein illustrated is as follows: Assuming that the body 1 is in the position shown, and that it is desired to dump the body: the cable 11 is would upon the drum 12, as by means of the crank 13, initial movement of the cable 11 being highly effective to pull down the rear end of the body 1 through the breaking of the toggles 5, 6. It will be seen that the initial movement is accomplished with little effort, because of the peculiar arrangement of the toggles with respect to the load, and that as soon as the toggle is moved an appreciable distance, the body 1 begins to dump the contents thereof so that the load is lightened as increased effort on the cable 11 is required.

This form of the invention is open to the objection that it imposes additional strain upon the pivot 3, but in many cases such additional strain may be easily taken care of.

In Figures 2 and 3 I have shown a modified form of the invention, in which the objection above mentioned is obviated. In this case, the lifting mechanism is mounted forward of the pivot 3, and it comprises on each side of the body a strut 16 mounted upon the frame member 2, and a strut 17 mounted on the body 1. The toggle comprising an upper arm 18 and a lower arm 19 is mounted between the struts 16 and 17. The arm 18 is pivoted at its upper end at 20 t0 the top of the struts 16, and the arm 19 is pivoted at its lower end to the lower end of the Struts 1'7 at the point 21. The two links 18 and 19 are pivoted to each other at the common point 22. Cables 2% are connected to the'pivots 22 and 22 of the respective knuckles on each side of the device. The cables 2% may be wound upon the drum 12 by any suitable power device, as, for instance, the crank 18 operating through the gears 14 and 15.

If desired, suitable guides may be provided for guiding the body and frame with respect to each other, and to relieve the struts 16 and 17 of the horizontal pull which would otherwise be imposed upon them. This latter provision is, however, optional.

The two forms may be combined, if desired, that is to say, a toggle in front of the pivot 3 may be combined with a toggle back of the pivot, and the central pivots drawn together by a cable, screw, rod, or the like. i

In Figure 1- 1 have shown a modified form of toggle, in which one of the arms 25 is extended as shown at 26, to form an operating lever for breaking the toggle. The arms 25 and 27 are pivoted to each other at 28,

and to the frame and body, as at 30 and 29, or vice versa. If desired, the operating arm 26 may be formed in the shape of a sector, so that a constant leverage of the arm 26 upon the toggle may be provided, the cable 31 then being trained over the periphery of the sector.

I do not intend to be limited to the details shown and described, as I shall direct my claims to the fundamental structures involved.

I claim:

1. In combination, a frame, a superposed load, a pair of co-operating struts one connected on the frame and one connected to the load, a pair of toggle links connected be--. tween said struts, said links being normally at a maximum angle with respect to each,

other when the load is down, and at a minimum angle with respect to each other when the load is raised, and means for applying power to said toggle arms to raise the load.

2. In combination, a frame, a load pivoted thereto, a pair of toggle links'pivoted to each other and to the frame and load respectively, said links being substantially in line with each other to form a toggle for locking the load to the frame, one of said links having an extending arm to which power is applied for breaking the toggle to raise the load about said pivo-t.- V

In witness whereof, I hereunto subscribe my name this 21st day of Man, A. D., 1921'.

JOHN A. DIENNER. 

